Gravity return system



April 14, 1931. R. B. HOBSON GRAVITY RETURN SYSTEM Filed Oct.

v a U 56 .E

ATTORNEY Patented Apr. 14, 1931 RUSSELL B. EOZBSON, OF MONTGLAIR, NEW JEItSEY GRAVITY RETURN SYSTEM Application filed October 11, 1926. Serial No. 140,834. 7

" My invention relates to a system for entraining liquids, such as water, by means of gas or vapor and it has for its object to provide apparatusjof the character deslgnated which may be more readily installed and maintained than similar devices now in use and which shall furthermore be highly effective to perform the desired functions under a wide variety of operating conditions. s t

i More specifically, my invention relates to a modified and improved form of receiver for use in connection with the well-known Holly gravity return system which is described in Gebhardts Steam Power PlantEngineering, New York, 1925, at pages 703, 704:) and toa systemof piping to gsaidhreceiver whereby. condensate drips maybe efliciently recovered from pressure zones ofslightly diflerent pressures.

' In the accompanyingdrawing, I show in Fig. 1 a diagrammatic vlew of a Holly gravity return system embodyinga receiver and receiver piping constructed in accordance with my invention; Fig. 2 is an enlarged sectional view of the receiver indicated in Fig; 1 and Figs. 3 and 4 are enlarged sectional views of modifiedtypes of entraining nozzles adapted for use in the receiver of Figs. 1

" piping system from the high pressure zone .75

and 2. I

. The. Holly system, briefiyspeaking, comprises a rece1ver,placed at a low'level, such that thehigh pressure drips flow thereto by gravity. These drips are carried upward to a discharge chamber provided at a sufficient altitude above the boilers to permit a column of water of considerable height between the same and the boiler. Within this discharge chamber, the air and steam-separate from 40 the water content which returns to the boiler,

the air and vapor being withdrawn through a vent pipe as to a heater, as is well known inthe art. I

In the past, the receiver construction usually employedhad joints or piping at the one form of bottom of the receiver, and due to the fact that these devices areefrequently placed inpits or other depressedpositions, they are inaccessible for the purposes of renewals or repairs and are subject toleakage or corrosion from without.

In accordance with the present invention, I mount theare ceiver at: a suitable low point for the collection of the high pressure drips, and I tap the riser throughthe upper side 55. thereof, the said riser terminating within the receiver in a U-shaped or other return bend entraining nozzle, open at one end, and, provided with fluid admitting perforations on one side thereof toward the bottom.

By this means, the entrainer may be readily connected or disconnected, is not subject to corrosion, or breakage, and has; no inac cessible parts.

If it be attempted a: collect drips from ,5

zones of slightly different pressure, such, for example, as the ends of a long run ofsteampipe wherein considerable pressure drop takes place, it will be found that with simple connections to the Holly receiver, there will either be wastage of steam at the high pres sure end or insuific'ient removal of drip from the low pressure end. Under these conditions I may insert atrap or U-tube in the to the receiver such that a water column 1s opposed tofthe flow. of drip from said high pressure end. I accordingly set up a slight back pressure, due to the unbalanced water column in said U-tube, th-is back pressure 30 being suflicient to eliminate the effect of the excess pressure in thest'eam pipe... By this means I am enabled'to properly drain vari? ous zones of slightly difierent high pressure to a common receiver, the relative rates of 35 dralnlng' being rendered independent of the" various highpressures. As, an opt mum condition, all of theflventingsteam should be drawn from the drainage point of lowest pressure, since this steam has, in general, a

boiler. Under these conditions, the drainage from said higher pressure points through said U-tubes is solely water, all gases and vapors being held back by the entrapping action of the U-tubes.

In the accompanying drawings is shown a boiler 6 delivering steam by a main 7, 8, to devices where. it is to be used, such as a steam chest 9-, and other devices (not shown). The purpose of the present invention is to provide for the automatic return to the boiler 6 of the condensed water from the main 7, 8, and from the devices drawing steam therefrom. For this purpose the steam chest 9 is connected by a drip line 13 to a Holly receiver 10 where the drip water collects. Here the drip water collects in the bottom, firstfilling a depression 24. Accompanying the drip,

water,and forming from it by the reduction in pressure at this point remote from the boiler, is considerable steam. The steam lies 7 above the water in the receiver 10 and escapes at the top through the upper open'end 23 of a U shaped discharge member 17. As it escapes, it e'ntrains the drip water through one or more perforations 23 and as it flows around the bottom 22 of the U, the water is carried along with it out the riser line l6'to a discharge chamber or separator 17. The separator 17 is located well above the boiler 6, so that the water separated out in the separator 17 forms a column of considerable height in the return. line 18 leading to the boiler 6. As aresult, the effective pressure on the riser line 16 is less' than that on the main 8 by the weight ,otthe water column in the re- 7 turn line 18, thus providing for a difference in pressure'which causes the escape of steam through the upper end 23 and the riser line 16. The air and uncondensed vapors leaving the separator 17 escape through a line 20 to a 5 point Where their heat can be usefully employed, as a feed-water heater 21.

In addition to the drip line 13, there may be other drip lines 11 and 12, coming, if desired, from points where the steam pressure is different. For enabling these drip lines to all feed into a single Holly receiver 10 there maybe interposed in each a U leg 14 or 15 of such length as to provide a column of trappedwatersufficient to partially or wholly equalize any difference in pressure from any other drip line. These legs 14 and 15 may be provided with checlrvalve 15 at the bottom to prevent surging of the water.

The discharge member 17 is internally threaded at the top to receive the lower end of the riser line 16, and is externally threaded to fit the threaded opening in the top of the 'Holly'receiver through which it is inserted,

thus providing a unitary devicewhich is easily removable, as for cleaning. the receiver 10, It often found advisable to have the at 31. A hollow frustro-conical member 32 V is seated upon" the member 30, its major base resting thereupon, and the member 32 is flanged at both its upper and lower ends for attachmentto the member 30 and t0 riser line 33. A hollow tubular member 34: has its openupper end 35 joined to the interior of the member 32 as by welding as indicated at 36andhasit's lower end closed except for fluid entraining orifices such as shown at 3737. A septum 38 is fastened to the inner surface of the wall 3 l'adjacent. the-upper end thereof and projects'downwardly'therein nearly to the lower end, dividing the space within the member 34cgintotwo separate passages .89 and 40, as indicated. Adjacent the upper end of the passage 40 a large orifice ll for the entry of air and gas is provided.

Referring'to Fig. 4, Ishow still another 7 form of entraining nozzle which is symmetri cal in form and which I have found well adapted to perform the desired function.

The member 25 is adapted tobesc'rewed into the wall of the receiverIO and has a centrally threaded orifice for the receipt of the riser line 16. A depending flange 26 defines a central passage from the riser line 16 to a point adjacent the bottom of a casing 2'",

also depending from the member 25 and 7 closed at its lower end except for small fluid entraining orifices 2828. The casing ,27

further contains air andvap r admitting ori fices 2929 adjacent its upper end.

In the structure shown in Figure 3 the riser line leading to. the separator is shown at 33 Into this the'st'eam in the Holly receiver 10 enters by Opening flowing first downward past the openings 37 where it entrains water, then around the bend 37 and up the riser line 31. I i

The structure shown in Figu're'tis adapted to be screwed into a Holly receiver 10, so that the steam leaving by the riser line 16' enters through large openings 29, passes downward outsidev the .fiange 26 1 entraining water throughthe smaller openings 28 and then upward through the riser line 16..

lVhile I have described'my invention in a plurality of modifications, it will be obvious to those skilled in the art that it is not limited to such modifications and I desire, therefore,;

that only such limitations be placed thereupon as are imposed by the prior art or specifically pointed out in the appended claims.

means tending to produce and maintain a low-er pressure in saidprojecting member than within the interior of saidreceiver.

2. In a device for entraining a liquid by av gas or vapor, the combination-with a closed container, of means for supplying. to the mterior thereof said liquid and said gas or vapor, a suction tube projecting through the top of said receiver and downwardly into close proximity to the bottom thereof, thence laterally and upwardly into proximity to the top thereof, terminating in a large gas and vapor admitting orifice, said upwardly-extending portion further being provided with a plurality of small liquid-admitting lateral orifices.

3. The combination with a receiver for a Holly gravity system of a suction tube projecting through the top thereof, downwardly into proximity to the bottom thereof, thence laterally and upwardly into proximity to the top thereof and terminating in an open end, said upwardly projecting portion being provided with a plurality of liquid admitting perforations. I V

I 4; The combination with a receiver for a Holly gravity system of a suction tube projecting through the top thereof, downwardly into proximity to the bottom thereof, thence laterally and upwardly into proximity to the top thereofand terminating in an open end,

said upwardly projecting portion being provided with a plurality of liquid-admitting perforations and said laterally extending portion being provided with at least one liquid-admitting perforation.

5. A receiver for a Holly gravity system comprising a horizontally disposed cylindrical tank provided with a drainage depression in the bottom thereof,a suction tube projecting through the top thereof and downwardly into said depression, thence laterally and upwardly above the normal fluid level,terminating in a large gas and vapor admitting orifice, said upwardly projecting portion being provided with a plurality of small fluidadmitting orifices and said laterally projecting portion being provided with at least one fluid-admitting orifice adapted to withdraw fluid from said depression. 7

6. In a collecting system for condensate drips, the combination with a boiler and a a 7 .:In a' collecting system receiver'adapted to collect drips from two zones of differing higherpressures, of a direct connection from said recelver to the zoneof lower pressure and a connection, including=a- U'-tubehaving two legs abovethe receiver, from'said receiver to said-zone of higher pressure, whereby an opposing-hydrostatic-pressure is set up in said U-tube equivalent to the difference of pressure between said two zone-s.

drips, -the'combination with a boiler and a receiver adapted to collect drips from two zones of differing higher pressures, of a direct connection from said receiver to the zone for condensate I of lower pressure and a connection, includ- 7 ing a U-tube having two legs above the receiver having a checkvalve at the bottom I thereof, from said receiver to the zone of higher pressure. I

8. In a collecting system for condensate drips, the combination with a boiler and a receiver adapted to collect drips from two zones of differing higher pressures, of a direct connection from said receiver to said zone of lower pressure and a connection from sald-receiver to said zone of higher pressure includf ing means above the receiver foracoumulating hydrostatic back pressure for compensating for the excess of pressure therein,

whereby the rates of drip collection from said I .two zones are rendered independent of the,-

differing pressures therein. 7

f). In a collecting system for condensate drlps, the combination with a boiler and receiver adapted to collect drips from a pluralion ity of zones of differing-higher pressures, of means for developing back pressures propor tional to the excess of ressure in each zone, whereby the rates of drip collection from the respective zones are rendered independent of the difiering pressures therein.

10. In a collecting system for condensate drips, thecombination with a boiler and receiver adapted to collect drips from a plurality of zones of differing higher pressures, of means for developing back pressure proportional to the excess of pressure in each zone over said predetermined pressure, whereby substantially all venting steam and gases are drawn from the zone of lowest pressure and only liquids are drawn from the zones of lngher pressure.

sure drips, the combination with a receiver upper wall thereof, a hollow frustro-conical 11. In an entraining system for high presmember having its largerbase seated'upon said flange member and flangedat its upper and 'lower ends respectively for attachment to said flange member and to a conduit, a tubular member mounted within said frustroconical member and projecting downwardly into said receiver, said tubular member being open at its upper end and closed at its lower end: except for a relatively smallem training opening, a diaphragm extending downwardly within said tubular member and defining a. fluid passagev fromthe upper end' thereof: to a point adjacent the bottom there:

of, and thence upwardly-t0 a point adjacemn the upper end thereof and a. relatively large. orifice in said tubular member opening into said fluid passage adjacent said last, named 10 point. 1

' In testimony whereof, I. have hereunto, subscribed my name this; 5th day of Octoben RUSSELL B. HOBSON. 

